Apparatus for manufacturing paper yarn



March 1964 J. N. LANCASTER ETAL 3,

APPARATUS FOR MANUFACTURING PAPER YARN Filed NOV. 1 1962 FIGJ.

INVENTORS JAMES N. LANCASTER CHARLES H. PONDER BY flrtww, 5W)

ATTORNEYS United States Patent Qiifrce 3,122,873 Patented Mar. 3, 1964 3,122,873 APPARATUS FOR MANUFACTURING PAPER YARN James N. Lancaster, E. Main St., Stoneviile, N.C., and

Charles H. Ponder, 2807 Northampton Drive, Greenshoro, N.C.

Filed Nov. 1, 1962, Ser. No. 234,677 2 Claims. (Cl. 5732) The present invention relates to a method of forming paper yarn by severing narrow strips of paper fiom wide rolls and condensing and contracting the strips into uniform round yarn.

Paper yarn is made by condensing thin strips of paper by squeezing, rolling or twisting. Generally, the strips are first moistened since this softens the paper making it pliable so that it might be more readily formed and twisted into a round uniform yarn.

There are several techniques for condensing the flat strips of paper to form yarn. A simple condensing operation is disclosed by Leinveber in US. Patent 868,193. A lateral furling is described by Richter et al. in US. Patent 1,969,855. However, the most suitable technique is twisting or spinning as shown in US. Patents 868,193, 43,874, 446,926, 830,221 and Reissue Patent 1,817, preferably on a down-draft type ring twister, as described by Hamilton 2,407,926 and by Brockman et al. US. Patent 2,482,895. In many cases, the strips may be twisted after a preliminary condensing operation, which is also disclosed in US. Patent 868,193.

The strips of paper are made by slitting a wide Web of paper as it is unwound from a large roll. After being severed from the web, the strips may be fed to a condensing stage in a continuous operation or they first may be rewound to form narrow rolls commonly called cheeses. The cheeses may be stored or shipped for later condensing operations. The continuous operation should be preferred, since it avoids winding and unwinding of cheeses, but it has not been as satisfactory in certain commercial operations. In the cheese system, the strips of paper, after moistening, usually are passed through a forming die or trumpet, which compresses the paper to a rough yarn. Subsequent twisting gives a very good quality yarn which possesses a high degree of uniformity. However, the continuous system is not readily adaptable to the use of forming dies. In all yarn-forming operations, there are occasional breakages of the paper strips or partially formed yarn caused by the weakening of the paper by moisture. When there is a break, the free ends of the paper strip must be tied together, and it may be necessary to reinsert the paper through the forming die. This causes no difficulty in the cheese system. This is so because only one spindle is stopped on a twister when using the cheese method if a paper strip breaks. arate cheese; the length of time that this end is shut down is of no consequence since other ends which operate independently are not interrupted and there is sufficient time to thread the strip through a former. In contrast, on a continuous system, all of the spindles are supplied from one roll of paper. If an end breaks, the paper is still advancing through the slitters and a strip is supplied which is wet by the moistener, whence it simply falls to the floor. For this reason, time is of the essence in tying this strip to the yarn being pulled by the spindle. It is necessary to tie the ends of the broken strip quickly enough so as not to interrupt the running of the other, unbroken strips. Otherwise, it would be necessary to shut down the operation in which 60 or more strips may be runnnig. That is, it is sufficiently difficult to start the paper strip through a forming die and the time required Each spindle is supplied with paper from a sepr is so great that the continuous slitting and twisting operation would have to be interrupted. A break of one end of yarn would require interruption of the twisting of all of the 60 or more ends severed from a single web of paper. Consequently, forming dies have not generally been used on continuous slitting and twisting apparatus and the yarn produced has had a greater number of flat spots and has generally been of lower quality than yarn made by the cheese system.

In accordance with the present invention, it has been found possible to form the yarn before twisting so as to improve its quality in a manner which is adaptable to continuous slitting and twisting operations. Briefly stated, the method comprises passing the severed strips of paper over a roller while lifting the edges of moistened paper from the roller so as to curl them away from the roller and then promptly begin twisting before the paper strip becomes flat again. The lifting is achieved by a pair of outwardly-sloping collars on the shaft. The space between the collars is somewhat less than the Width of the paper strips so that, as the strip passes over the roller, its center is in contact with the roller but its edges are curled inwardly. A much higher quality yarn is produced which is more uniform and has fewer flat spots, and is of greater strength due to the strips being rolled eliminating exposed paper edges which break or tear. In addition, the degree of twist required to form a smooth, round yarn is reduced, which permits increasing the speed of operation.

The invention and its objects will be better understood by reference to the following detailed description of a preferred embodiment, and by reference to the drawings in which:

FIGURE 1 is a perspective view of the apparatus of the invention showing a strip of paper being formed and twisted;

FIGURE 2 is an elevation, partially in section, of a portion of the apparatus;

FIGURE 3 is a front view of the roller and sloping collars which form the yarn prior to twisting;

FIGURE 4 is a cross-section of the roller and sloping collars along lines 4-4 of FIGURE 3; and

FIGURE 5 is a front view similar to FIGURE 3 showing a strip of paper being formed and twisted.

A web of paper is slit into narrow strips by a multiple cutter of the type shown in US. Patent 1,969,855 and, after the strips are separated, each is moistened by passing over a wet roller which dips into a trough of liquid. The strips then pass over a roller 3 where they are formed and downwardly to a ring twister 4 which twists the strips and winds them on a bobbin 5.

The forming apparatus comprises the shaft 3 and a pair of collars 6 and 7 fixed to the shaft by set screws or other suitable means. Usually the shaft is driven by conventional means not shown. The collars have opposing radially and axially outwardly extending tapered faces 8 and 9 separated by a short length 10 of shaft 3 so that the strip of paper passes through a moving, generally V- shaped gap. The angle between the tapered faces 8 and 9 and the shaft 3 is about The exposed length of shaft at 10 is somewhat less than the width of the paper strip so that the edges of the strip are lifted and curled outwardly away from the shaft. For example, when the width of the paper strip is about .1875, the exposed length of shaft between the collars is about .0937.

After leaving this forming station, the yarn passes downwardly through eyelet 11 and through a traveler 12 which is mounted on a ring-shaped track in a vertically reciprocating, traversing mechanism 13. The yarn is then wound on a bobbin 5 which is turned by a spindle as is conventional in down-draft ring-twisters.

The resulting yarn is smooth and uniformly round with substantially no fiat spots; It is possible to achieve this result with a lower degree of twist than is required for a somewhat lower quality yarn when the collars 6 and 7 are not in use. Consequently, since the product rate of a twister increases as the degree of twist decreases, higher rates of production are achieved for this improved yarn. When there is a break in one end of the yarn, it is possible to tie the free ends of the yarn and reinsert the strip of paper in the former without stopping the continuity of operations.

Any type of paper web may be used, but it is preferable to use resin-treated, high wet strength paper sold as twisting paper. The moistening bath may also contain any of the known treating chemicals, wetting agents and waxes.

Various changes and modifications may be made in the details of construction and mode of operation of the preferred embodiment described such as providing at a slight curvature of the tapered lift faces of the collars 6 and '7 or using other kinds of conventional twisters where ap-' propriate and the like without departing from the scope of the invention, as defined in the claims.

What is claimed is:

1. In an apparatus for the continuous slitting and twisting of a paper web which comprises means for supporting and unwinding a roll of paper, slitting means for severing said web'into narrow strips of paper, means for moistening the strips of paper to facilitate shaping and twisting, and means for twisting said narrow strips; the improvement comprising means for shaping the strips of paper prior to twisting which includes a shaft, means for rotating said shaft and a pair of spaced collars fixed to said shaft for rotation, said collars having opposed axially and radially outwardly tapered faces such that the lateral edges of a strip of paper passing over said roller as it is rotated will be lifted from said roller and curled outwardly from said shaft, said shaping means being positioned to receive the substantiallyfiat strips from said moistening means and adjacent said twisting means so that paper strip leaving said shaping means does not be- 7 come flat after shaping and before twisting.

2. An apparatus for the continuous slitting and twisting of a paper web as set forth in claim 1 in which said twisting means is a down-draft type ring twister.

References Cited in the file of this patent UNITED STATES PATENTS 919,332 Dymock Apr. 27, 1909 2,196,923 Johanson Apr. 9, 1940 2,284,321 Kimball May 26, 1942 2,427,172 Williams Sept. 9, 1947 FOREIGN PATENTS 304,397 Germany Sept. 15, 1919 

1. IN AN APPARATUS FOR THE CONTINUOUS SLITTING AND TWISTING OF A PAPER WEB WHICH COMPRISES MEANS FOR SUPPORTING AND UNWINDING A ROLL OF PAPER, SLITTING MEANS FOR SEVERING SAID WEB INTO NARROW STRIPS OF PAPER, MEANS FOR MOISTENING THE STRIPS OF PAPER TO FACILITATE SHAPING AND TWISTING, AND MEANS FOR TWISTING SAID NARROW STRIPS; THE IMPROVEMENT COMPRISING MEANS FOR SHAPING THE STRIPS OF PAPER PRIOR TO TWISTING WHICH INCLUDES A SHAFT, MEANS FOR ROTATING SAID SHAFT AND A PAIR OF SPACED COLLARS FIXED TO SAID SHAFT FOR ROTATION, SAID COLLARS HAVING OPPOSED AXIALLY AND RADIALLY OUTWARDLY TAPERED FACES SUCH THAT THE LATERAL EDGES OF A STRIP OF PAPER PASSING OVER SAID ROLLER AS IT IS ROTATED WILL BE LIFTED FROM SAID ROLLER AND CURLED OUTWARDLY FROM SAID SHAFT, SAID SHAPING MEANS BEING POSITIONED TO RECEIVE THE SUBSTANTIALLY FLAT STRIPS FROM SAID MOISTENING MEANS AND ADJACENT SAID TWISTING MEANS SO THAT PAPER STRIP LEAVING SAID SHAPING MEANS DOES NOT BECOME FLAT AFTER SHAPING AND BEFORE TWISTING. 